WLED Current up to 60mA per String
PWM Dimming Control from 100Hz to 20kHz
LED Power Sequence Control Free
Boost Output Voltage Adjustable up to 16V
Programmable Soft-Start
Fault and Thermal Protection
Up to 350mA LDO
35V High Voltage Switch for VGHM
Positive Charge Pump for Gate-High Supply
640kHz/1.2MHz Switching Frequency for AVDD
600kHz to 2MHz Switching Frequency for LED
VCOM Operational Amplifier
Reset Signal Output for T-CON
WQFN 40-5 x 5 Package
General Description

The AAT1223 is a single-chip solution for TFT LCD panel application. It contains multi-channel TFT LCD power solution that provides a boost PWM regulator, positive charge pump, VCOM operational amplifier, voltage detector, low dropout linear regulator, GPM controller up to 35V for TFT LCD display, and WLED backlight driver.
The LED driver can drive 4 strings of WLEDs using constant current source. The mismatch current of every string is within 3%.
The PWM controller consists of an on-chip voltage reference, oscillator, error amplifier, current sense circuit, comparator, under-voltage lockout protection and soft-start control circuit. The thermal and power fault protection prevents excessive power from damaging the internal circuit.
The positive charge pump generates VGH voltage (gate high voltage) setting by external resistor divider. For the flicker compensation, VGHM will be connected to VGH when VFLK is low and connected to RE when VFLK is high. In addition, AAT1223 contains one operational amplifier capable of supplying 150mA to VCOM.
With minimal external components, the AAT1223 offers a simple and economical solution for TFT LCD and backlight power management.